French Pat. No. 74 36 378, published under No. 2 290 126, and its certificate of addition No. 75 33 425, published under No. 2 346 939, propose using microwaves to excite a plasma in a column of gas contained in an elongate tubular member.
Otherwise, although attempts have been made over a long period of time to obtain a laser effect in a gas excited by microwaves, such a laser effect has not been observed heretofore. This is in spite of the fact that much research has been directed towards obtaining a laser of sufficient power and longterm stability for the laser to be useful in industrial applications.
Preferred implementations of the present invention solve this problem.
This is achieved firstly by increasing the energy density provided by apparatus of the type described in the above-mentioned patent and certificate of addition, and secondly by providing an ion laser structure which is based on such apparatus, as a particular application of the invention.
The invention also makes new laser effects possible, concerning both the spectrum lines which are emitted and the relative powers of said lines. This is particularly true of a krypton-argon ion laser which emits both a red spectrum line and a blue spectrum line.